System and method for value based region searching and associated search operators

ABSTRACT

Embodiments as disclosed herein allow simple specification of searches of values within regions and efficient implementation of such searches. Specifically, embodiments as disclosed may provide a search operator that addresses the problem of complex query construction for finding objects having a particular value, including a minimum or a maximum value, in one of a set of regions, and the efficient implementation of the searches specified by such search operators.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of, and claims a benefit of priorityunder 35 U.S.C. 120 from, U.S. patent application Ser. No. 16/628,942filed Jan. 6, 2020, entitled “SYSTEM AND METHOD FOR VALUE BASED REGIONSEARCHING AND ASSOCIATED SEARCH OPERATORS,” which is a national stageapplication of and claims the benefit of priority to InternationalApplication No. PCT/CA2018/050818, filed Jul. 5, 2018, entitled “SYSTEMAND METHOD FOR VALUE BASED REGION SEARCHING AND ASSOCIATED SEARCHOPERATORS,” which claims a benefit of priority under 35 U.S.C. § 119(e)to U.S. Provisional Application No. 62/529,345, filed Jul. 6, 2017,entitled “SYSTEM AND METHOD FOR VALUE BASED REGION SEARCHING ANDASSOCIATED SEARCH OPERATORS,” which are hereby incorporated herein forall purposes.

TECHNICAL FIELD

This disclosure relates generally to search engines. More particularly,this disclosure relates to systems and methods for search engines thatfacilitate specification of complex search queries using simpleoperators and are capable of efficient implementation of these queries.

BACKGROUND

A search engine is a computer program used to index electronicallystored information (referred to as a corpus) and search the indexedelectronic information to return electronically stored informationresponsive to a search. Items of electronic information that form thecorpus may be referred to interchangeably as (electronic) documents,files, objects, items, content, etc. and may include objects such asfiles of almost any type including documents for various editingapplications, emails, workflows, etc. In a conventional search engine, auser submits a query and the search engine selects a set of results fromthe corpus based on the terms of the search query. The terms of searchqueries usually specify words, terms, phrases, logical relationships,metadata fields to be searched, synonyms, stemming variations, etc.

Generally, there are two basic methods for selecting a set of resultsfrom a corpus based on a search query. In the first method, an item thatmeets the explicit search terms of the search query will be selected.Only items of the corpus that meet the explicit requirements of thesearch terms are selected and presented. In the second method, for sometypes of applications, the set of results selected is constrained (orfurther constrained) by a relevance measure. In particular, resultsselected by evaluating a search query as an explicit query are furtherscored and ordered by some criteria, and only the highest results areselected. Relevance scoring may incorporate variables such as thefrequency of terms, weights on results with certain values or inspecified metadata fields, distance from a value or a date, similarityto other results or objects, etc.

These types of searches may be employed in various different contextsand for various different purposes; however, in certain contexts one orthe other type of search may prove more or less useful or apropos for acertain task. Certain areas have, however, proved difficult to theapplication of searches of either type. Examples of such searchesinvolve searches of certain fields (or regions) where the fields may, ormay not, exist for particular documents within the corpus.

When employing search in association with such systems that may maintainregions, determining the meaningful regions to search and which tosearch may be difficult as these fields may or may not exist or bepopulated with respect to different documents in the corpus.Accordingly, it may be desired to search objects based on the valueswithin these regions, accounting for the presence (or lack of) a valuein these regions, or a priority of these regions.

Traditional search systems do not support the ability to conduct thesetypes of searches. Thus, to implement a search of this type a user mustconstruct a search query that explicitly enumerates each of the possiblealternatives. This enumeration process is complex and not easilyunderstood or accomplished by most users. Moreover, these searches (evenwhen optimized) tend to be inefficient. Accordingly, the implementationof a search according to such search queries by typical search enginesmay consume large quantities of time, memory or other computerresources. In some cases, for certain queries, the resources requiredfor a particular query may exceed the computing resources available ormay require that certain computing resources be taken off-line anddedicated to the search in order to complete such a search.

What is needed, therefore, are systems and methods that allow simplespecification of searches of multiple of regions based on the valueswithin those regions, and that efficiently implement such searches.

SUMMARY

To those ends, among others, embodiments as disclosed may provide asearch operator that addresses the problem of complex query constructionfor finding objects having a particular value in one of a set of regions(e.g., one or more specified regions), where any values present in theset of regions may be used to determine the responsiveness of the objectto the search. Before describing embodiments in more specificity, someadditional context may be useful. As discussed, a search engine is acomputer program used to index a corpus and search the indexed corpus toreturn objects responsive to a search. In a conventional search engine,a user submits a query and the search engine selects a set of resultsfrom the corpus based on the terms of the search query. The terms ofsearch queries usually specify words, terms, phrases, logicalrelationships, metadata fields to be searched, synonyms, stemmingvariations, etc.

Certain areas have, however, proved difficult to the application ofsearch. Examples of such searches involve searches of certain regionswhere the regions may, or may not, exist for particular documents withinthe corpus. For instance, in many content management systems, theobjects may have many different fields (e.g. metadata fields) associatedwith each object. Oftentimes these regions are sparsely populated andmay have similar or related meanings. Consider the following metadataregions that may be maintained by a content management system such asOpenText's Content Server:

FileCreated Date the document was created, as recorded by the filesystem on a user's computer. FileModified Date the document was lastmodified, as recorded by the file system on a user's computer.DateManaged Date the first version of a document was added to theContent Server. VersionCreated Date the most recent version of thedocument was added to the Content Server. PaperDate Date a document wascreated, perhaps typed. May be much earlier than a FileCreated date ifthe original typewritten document was later scanned. FormatDate A datefield stored in a document as part of the file format. For example, aMicrosoft Word document might keep its own internal value for creationdate or modified date.

For each document in a content management system, these regions may beoptional and may be sparsely populated.

Generally, then, when employing search in association with systems suchas these that maintain regions, determining the meaningful regions tosearch and which regions to search, may be difficult as these fields mayor may not exist or be populated with respect to different documents inthe corpus. Examples of these areas include searches of a corpus ofdocuments in conjunction with litigation discovery or compliance. Inparticular, continuing with the above example with respect to themetadata fields of a content management system, there may be situationswhere it is desired to search based on meaningful dates (e.g., documentsolder or younger than 10 years, documents created over three years ago,etc.).

As the different regions pertaining to dates of a document may or maynot be present, it may be desired to search a set of regions pertainingto the date of a document. Again continuing with the above example, ifit is desired to find documents younger than 10 years in a contentmanagement system having the metadata fields listed above it may bedesired to search these regions such that any documents having a valuefor any date in any of these regions that is younger than 10 years willbe deemed responsive to these search.

Now suppose it is desired to search for documents older than ten yearsin a content management system having the regions defined above usingthe priority of regions PaperDate, FileModified, FileCreated, FormatDateand DateManaged. This search may be outlined as follows:

-   -   For each object in the index        -   The OldestDate is the minimum of the values in the            PaperDate, FileModified, FileCreated, FormatDate, and            DateManaged fields        -   If the OldestDate is more recent than 10 years            -   Add the object the set of matching results

Traditional search systems do not support the ability to conduct thesetypes of searches. Thus, to implement a search of this type, a user mustmanually construct a search query that explicitly enumerates each of thepossible alternatives. This enumeration process is complex and noteasily understood or accomplished by most users. Moreover, thesesearches (even when optimized) tend to be inefficient from acomputational and computer resource standpoint. Accordingly, theimplementation of a search according to such search queries by typicalsearch engines may consume large quantities of time, memory or othercomputer resources. In some cases, for certain queries of this type, theresources required for a particular query may exceed the computingresources available, or may require that certain computing resources betaken off-line and dedicated to the search in order to complete such asearch.

Continuing with the above example, an enumerated search to finddocuments that are 10 years old when considering all the relevant datefields in a content management system having the metadata fields listedabove may be:

-   -   ((PaperDate=10 years or PaperDate=null) and (FileModified=10        years or FileModified=null) and (FileCreated=10 years or        FileCreated=null) and (FormatDate=10 years or FormatDate=null)        and (DateManaged=10 years or DateManaged=null)) and        ((PaperDate=10 years) or ((FileModified=10 years) or        (FileCreated=10 years) or (FormatDate=10 years) or        (DateManaged=10 years))).

As another example, suppose a content management system maintains anassociated region for a creation date, a modified date, an embeddedproperties date, a record date (when it was declared a formal record),and a system date it was added to the document management system.Furthermore, these dates may be independently optional or sparse.Further suppose that in such a system a user needs to find documentsthat are more recent than 5 years old. To accomplish this, they want toidentify documents where the oldest (or minimum) value of any of thesedates is more recent than 5 years in age. A query to accomplish this isvery complex, and prone to user error. The query would be of the form:((FileCreated>−5y or FileCreated is undefined) and (FileModified>−5y ormodified is undefined) and (embedded>−5y or embedded is undefined) and(record>−5y or record is undefined) and (system>−5y or system isundefined) and ((created>−5y) or (modified>−5y) or (embedded>−5y) or(record>−5y) or (system>−5y)).

Moreover, the basic form of the necessary query varies depending onwhether minimum or maximum values need to be tested, and whether thecomparison operation is for equality, inequality, greater than or lessthan—or for search text matches such as “contains”. In general, usersare unable to construct a query reliably. This may lead to errors, butmore often to lost opportunity as users will not even attempt to workwith sets of regions due to the complexity.

Although such a search may be constructed explicitly by an extremelyknowledgeable user, these types of search are inefficient, sometimesneeding 5n−1 terms to evaluate when there are n regions being assessed.Even in cases where such a query may be refactored or optimized or is abest case scenario, such an optimized search query may be on the orderof a high coefficient linear search (e.g., around or greater than 2n−1).Thus, not only are such searches extremely difficult for a user toconstruct, but even if they can be constructed, they result in a largeconsumption of computing resources, including processing time andmemory.

Thus, while the user experience could be made easier by automaticallyconverting a simple syntax to the complex equivalent to address usererror, such a solution does not improve the computing resources or querycomplexity which are provided by the invention.

A new searchable region (metadata field) which logically contains theminimum or maximum values of all the metadata regions of interest couldalso be created. As items are added to the index, removed from theindex, or modified, the value contained in the minimum or maximum fieldwould be reassessed and updated. The resulting query would be easier forthe user to create, and fast to execute. However, this approach hasseveral drawbacks. Firstly, there is a performance penalty duringindexing to update these fields. Secondly, there is a size/space penaltyin the index—since a new region must be maintained along with storage ofvalues and associated index structures. More importantly, theadministrator of the system must know a priori which minimum or maximumfield definitions need to exist, and only those pre-configured scenariosmay be used.

What is needed, therefore, are systems and methods that allow simplespecification of searches of multiple regions for maximum or minimumvalues and that efficiently implement such searches.

To those ends, among others, embodiments as disclosed may provide asearch operator that addresses the problem of complex query constructionfor finding objects having a minimum or maximum value in a set ofregions. These search operators may allow the specification of minimumsearch or a maximum search. Such searches may specify a minimum (min)search or a maximum (max) search, a set of regions to be searched, and asearch value including a comparator to utilize (e.g., >,<, =, <=, >=,!=, etc.) and a value. In effect, these search operators may be used toconstruct a synthetic region type in a search engine. In other words, aregion that may not be indexed or stored in the metadata for documentsin a content management system. Such a synthetic region may be amulti-source region that is made up of one or more traditional regions(e.g., regions that are indexed or whose values are otherwise stored inthe metadata (or otherwise) for a document in the content managementsystem. Thus, values for the synthetic region are not stored explicitly,rather they are determined by the underlying regions.

Thus, for example, for a maximum search the search operator syntax maybe as follows:

-   -   Maximum    -   [max r1, r2, r3]>x    -   Equivalent to: r1>x OR r2>x OR r3>x    -   (same for >=e.g., r1>=x OR r2>=x OR r3>=x)    -   [max r1, r2, r3]<x    -   Equivalent to: ((r1<x or r1 is NULL) AND (r2<x or r2 is NULL)        AND (r3<x or r3 is NULL)) AND (r1<x OR r2<x OR r3<x)    -   (same for <=)    -   [max r1, r2, r3]=x    -   Equivalent to: ((r1<=x or r1 is NULL) AND (r2<=x or r2 is NULL)        AND (r3<=x or r3 is NULL)) AND (r1=x OR r2=x OR r3=x)    -   [max r1, r2, r3] !=x    -   Equivalent to: (r1!=x AND r2!=x AND r3!=x) OR (r1>x OR r2>x OR        r3>x)

For a minimum search the search operator syntax may be as follows:

-   -   Minimum    -   [min r1, r2, r3]<x    -   Equivalent to: r1<x OR r2<x OR r3<x    -   (same for when the comparator is <=, e.g., r1<=x OR r2<=x OR        r3<=x)    -   [min r1, r2, r3]>x    -   Equivalent to: ((r1>x or r1 is NULL) AND (r2>x or r2 is NULL)        AND (r3>x or r3 is NULL)) AND (r1>x OR r2>x OR r3>x)    -   (same for >=)    -   [min r1, r2, r3]=x    -   Equivalent to: ((r1>=x or r1 is NULL) AND (r2>=x or r2 is NULL)        AND (r3>=x or r3 is NULL)) AND (r1=x OR r2=x OR r3=x)    -   [min r1, r2, r3] !=x    -   Equivalent to: (r1!=x AND r2!=x AND r3!=x) OR (r1<x OR r2<x OR        r3<x)

Thus, embodiments as disclosed may provide a simple syntax for users inthe instance where a user desires to search for a minimum or maximumvalue in a set of regions that may (or may not be) sparsely populated.In certain embodiments, a maximum region will only match for a givenobject if the maximum value of all the set of regions (that have avalue) for that particular object matches the query, likewise a minimumregion requires the minimum of the values of the set of regions to matchfor any given object. As an example, an equivalent query to the 5 yeardate query discussed above utilizing embodiments as contemplated hereinwould be:

-   -   [min created,modified,embedded,record,system]>−5y

Accordingly, one benefit to using a maximum or minimum region operatoraccording to embodiments (over traditional regions or searches) is the(lack of) complexity of the resulting query. Without maximum and minimumregions the queries become quite complex and tedious to compose. Themaximum and minimum regions are also able to return the matching valuein a select statement, which would require all underlying regions to bereturned and post processing with the traditional query. Of note, here,embodiments may not simply transform this syntax into a functionalequivalent to reduce user error. Embodiments may permit ad hoc queryconstruction on any combination of searchable regions without requiringpre-configuration.

Embodiments as presented herein may thus have a number of advantages. Byimplementing such a region value search, the search problem of searchinga set of regions that may be sparsely populated may be solvedefficiently at the process and search tree level as opposed to at thequery level (e.g., by expanding such a query manually, or expanding itthrough automatic syntax rewriting). Accordingly, embodiments may avoidthe need to execute such huge queries and provide many technicalimprovements in the functioning of the computer when applying suchregion value searching, including the use of fewer computer resourcessuch as disk accesses, memory or processor cycles and reducing the timeneeded to execute such a search. Moreover, embodiments of such searchoperators may be usefully applied in a variety of contexts.

Additionally, embodiments as disclosed may improve the functioning of acomputer, both from a processing efficiency standpoint, a speedstandpoint and a computer resource usage standpoint by utilizing fewer(and faster) processes that reduce time of execution, number of computecycles required for execution and memory usage required for execution.Moreover, embodiments may also implement the minimum and maximumfunctions more efficiently than their optimized fully expandedequivalents. To illustrate, in the example above, the optimal fullyexpanded query requires 24 iterators, or 5n−1 (where n is the number ofregions). The new minimum operator performs the same query using only 2n(or 10) iterators. This reduction in iterators allows a search query tofunction using fewer resources, such as CPU memory, which in turn canreduce the cost of the solution or permit more complex operations tocomplete within an available CPU and memory budget.

Generally, then the number of iterators required for differentpermutations of the minimum and maximum (min/max) region operators maybe as follows and are presented in comparison with the number ofiterators typically required for such a search previously:

Maximum Search Minimum Search Previously Embodiments PreviouslyEmbodiments < (or <=) 5n − 1 2n 2n − 1  n > (or >=) 2n − 1  n 5n − 1 2n= 5n − 1 2n 5n − 1 2n != 4n − 1 2n 4n − 1 2n

Moreover, embodiments may also be utilized to return the region orregions used in matching the query. From a functionality and usabilitystandpoint, embodiments may also have the advantage of simplicity: usersare more likely to construct a useful and meaningful search when asimple operator for their desired functionality is available, as opposedto having to construct long and complicated manual queries.

These, and other, aspects of the invention will be better appreciatedand understood when considered in conjunction with the followingdescription and the accompanying drawings. The following description,while indicating various embodiments of the invention and numerousspecific details thereof, is given by way of illustration and not oflimitation. Many substitutions, modifications, additions orrearrangements may be made within the scope of the invention, and theinvention includes all such substitutions, modifications, additions orrearrangements.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings accompanying and forming part of this specification areincluded to depict certain aspects of the invention. A clearerimpression of the invention, and of the components and operation ofsystems provided with the invention, will become more readily apparentby referring to the exemplary, and therefore non-limiting, embodimentsillustrated in the drawings, wherein identical reference numeralsdesignate the same components. Note that the features illustrated in thedrawings are not necessarily drawn to scale.

FIGS. 1A and 1B depict example search trees.

FIG. 1C depicts one example of a search tree for an example use of aregion value operator.

FIG. 2A is a block diagram of one embodiment of an architectureincluding a search system.

FIG. 2B is a block diagram of one embodiment of an object analyzer.

FIG. 3 is a block diagram one embodiment of a search system.

FIG. 4 is a block diagram of one embodiment of regions or fields for aportion of an index.

FIG. 5 is a block diagram of one embodiment of an indexing engine.

FIG. 6 is a block diagram of one embodiment of an index with multiplepartitions connected to and being managed by a partition manager.

FIG. 7 is a flow diagram depicting one embodiment of a method for aregion value iterator.

FIGS. 8A and 8B are tables illustrating example data.

DETAILED DESCRIPTION

The disclosure and various features and advantageous details thereof areexplained more fully with reference to the exemplary, and thereforenon-limiting, embodiments illustrated in the accompanying drawings anddetailed in the following description. It should be understood, however,that the detailed description and the specific examples, whileindicating the preferred embodiments, are given by way of illustrationonly and not by way of limitation. Descriptions of known programmingtechniques, computer software, hardware, operating platforms andprotocols may be omitted so as not to unnecessarily obscure thedisclosure in detail. Various substitutions, modifications, additionsand/or rearrangements within the spirit and/or scope of the underlyinginventive concept will become apparent to those skilled in the art fromthis disclosure.

As discussed, certain areas have, however, proved difficult to theapplication of searches. Examples of such searches involve searches ofcertain fields (or regions) where the fields may, or may not, exist forparticular documents within the corpus. For instance, in many contentmanagement systems the documents (objects) may have many differentfields (e.g. metadata fields) associated with each document. Often timesthese regions are sparsely populated and may have similar or relatedmeanings.

Generally, then, when employing search in association with such systemsthat may maintain regions, figuring out the meaningful regions to searchand which to search may be difficult as these fields may or may notexist or be populated with respect to different documents in the corpus.In particular, when a set of related regions may be present inassociation with each object, it may be desired to search the regionsbased on a desired maximum or minimum value for the set of regions suchthat if an object has regions present (e.g., a value populated for thatregion), it will be these values that will be utilized to evaluate theresponsiveness of that object to the search to determine if all thevalues in the regions meet the desired minimum or maximum value.

As traditional search systems do not support the ability to conductthese types of searches, to implement a search of this type in atraditional search system, a user must construct a search query thatexplicitly enumerates each of the possible alternatives. Thisenumeration process is complex and not easily understood or accomplishedby most users. Moreover, these searches (even when optimized) tend to beinefficient. Accordingly, the implementation of a search according tosuch search queries by typical search engines may consume largequantities of time, memory or other computer resources and may need onthe order of 5n−1 terms to evaluate.

Moreover, in actual practice, a search query may have many othercriteria (dates, metadata values, other text terms, etc.). As one canimagine, creating search queries for more complex scenarios will quicklyexceed a (searching) user's capacity to easily and correctly build asearch query. Some of the problems arise in no small part because in abinary tree approach to implementing a search, each binary operator ofthe search tree may be a node that includes two sub-nodes, where each ofthese sub-nodes may be either another operator node or may include asearch term node (e.g., as a leaf node). Thus, traditional searchengines construct search trees made up of unary or binary iterators inthe tree and term iterators at the leaves of the tree. Each termiterator's scope is limited to one term and each binary operator processis limited to two terms. Such constraints lead to extremely complexqueries, even for a small number of terms.

Accordingly, the implementation of such search queries by typical searchengines may consume large quantities of time, memory or other computerresources. In some cases, for certain queries, the resources requiredfor a particular query may exceed the computing resources available ormay require that certain computing resources by taken off-line anddedicated to the search in order to complete such a search. At least inpart, this situation may result from the manner in which these types ofsearches are implemented by typical search engines. As mentioned, mostsearch engines function by evaluating a search using a binary treeapproach where binary search operators are involved. To illustrate inmore detail, almost all search engines (e.g., full text search engines)maintain an index. This index may include, for example, an inverted copyof the indexed information. So, for example, assume that the corpus ofdocuments being indexed includes three documents with the followingvalues in a “Name” region:

-   -   Object 1—“Water, Rivers and Lakes”    -   Object 2—“Rivers, Dams and Rainfall”    -   Object 3—“Rivers and Ponds”

For the above example an inverted index (also called the posting list)for the “Name” region may look similar to:

-   -   And—1, 2, 3    -   Rivers—1, 2, 3    -   Lakes—1    -   Rainfall—2    -   Ponds—3    -   Water—1    -   Dams—2        -   Such an index indicates that the term “And” appears in            objects 1, 2 and 3, the term “rivers” appears in objects 1,            2 and 3, the term “lakes” appears in object 1, the term            “Ponds” appears in object 3, etc.

FIG. 1A depicts a representation of an example search tree for thesearch “(stream AND pond AND lake AND river AND water)”. Here, each termnode 102 represents a process that searches, determines and providesobjects of the corpus that includes the labeled term. In other words, aprocess may access the index to determine which objects of the corpusinclude that search term. For example, term node 102 a represents accessto the index to identify objects that include the term “stream”.Similarly, term node 102 b represents access to the index to identifyobjects that include the term “pond.” Operator node 104 a represents aprocess that will union or otherwise combine the objects returned by theprocess associated with term node 102 a and the process associated withterm node 102 b to determine the objects that contain both the term“stream” and the search term “pond”. As can be seen, the search “(streamAND pond AND lake AND river AND water)” requires at least five termprocesses 102 for the search terms and four binary operator processes104 for each of the operators.

As can be imagined from the depiction of this simple search, theassociated number of processes, associated computer power, memory, time,etc., quickly become untenable when discussing search queries like thoseenumerated above for sets of regions. To illustrate further, FIG. 1B isa block diagram depicting a representation of an example search tree forthe search “(stream AND pond AND lake AND river AND water) OR (creek ANDpond AND lake AND river AND water)”. As can be seen, the size andcomplexity of the search tree may grow rapidly based on the number ofoperators or permutations involved in the search, despite that thenumber of actual terms involved (e.g., water, river, lake, pond, stream,creek, rain, rainfall, dam) may be constant and relatively few innumber.

Embodiments as disclosed herein may address these deficiencies anddisadvantages by allowing simple specification of searches of sets ofregions for a minimum or maximum value and efficient implementation ofsuch searches. Specifically, embodiments as disclosed may provide asearch operator (generally referred to as a region value search oroperator, a min/max search or operator or minimum or maximum search oroperator) that addresses the problem of complex query construction forfinding objects having a minimum or maximum value in one of a set ofregions.

In other words, according to certain embodiment, a min/max search mayspecify a set of regions and a search value including a comparator and acomparison value. Such a search can determine based on any valuespresent in the set of regions if one or more of those values makes thecomparison (e.g., as defined by the comparator) with the comparisonvalue true. Moreover, embodiments as disclosed herein may efficientlyimplement the searches specified by such min/max operators using aregion value process that combines results from a set of regionprocesses where a maximum of two processes may be needed for each regionin the set of regions.

Embodiments of this region value operator may take almost any formdesired and be utilized with other operators traditionally used withsearch queries as are known in the art. The region value operator mayalso utilize almost any syntax desired to specify a search for findingobjects having a minimum or maximum value in one of a set of regions.Accordingly, region value search operators may also be provided incertain embodiments that allow region set of regions to be dynamicallydefined at the time of the search by the user. These search operatorsmay allow the specification of minimum search or a maximum search. Suchsearches may specify a minimum (min) search or a maximum (max) search, aset of regions to be searched, a comparator to utilize (e.g., >,<, =,<=, >=, !=, etc.) and a value. These search operators may be used toconstruct a synthetic region type in a search engine. In other words, aregion that may not be indexed or stored in the metadata for documentsin a content management system. Such a synthetic region may be amulti-source region that is made up of one or more traditional regions(e.g., regions that are indexed or whose values are otherwise stored inthe metadata (or otherwise) for a document in the content managementsystem.

Here, values for the synthetic region may not be stored explicitly,rather they are determined by the underlying regions.

Thus, for example, for a maximum search the search operator syntax maybe as follows:

-   -   Maximum    -   [max r1, r2, r3]>x    -   Equivalent to: r1>x OR r2>x OR r3>x    -   (same for >=)    -   [max r1, r2, r3]<x    -   Equivalent to: ((r1<x or r1 is NULL) AND (r2<x or r2 is NULL)        AND (r3<x or r3 is    -   NULL)) AND (r1<x OR r2<x OR r3<x)    -   (same for <=)    -   [max r1, r2, r3]=x    -   Equivalent to: ((r1<=x or r1 is NULL) AND (r2<=x or r2 is NULL)        AND (r3<=x or r3 is    -   NULL)) AND (r1=x OR r2=x OR r3=x)    -   [max r1, r2, r3] !=x    -   Equivalent to: (r1!=x AND r2!=x AND r3!=x) OR (r1>x OR r2>x OR        r3>x)

For a minimum search the search operator syntax may be as follows:

-   -   Minimum    -   [min r1, r2, r3]<x    -   Equivalent to: r1<x OR r2<x OR r3<x    -   (same for <=)    -   [min r1, r2, r3]>x    -   Equivalent to: ((r1>x or r1 is NULL) AND (r2>x or r2 is NULL)        AND (r3>x or r3 is    -   NULL)) AND (r1>x OR r2>x OR r3>x)    -   (same for >=)    -   [min r1, r2, r3]=x    -   Equivalent to: ((r1>=x or r1 is NULL) AND (r2>=x or r2 is NULL)        AND (r3>=x or r3 is    -   NULL)) AND (r1=x OR r2=x OR r3=x)    -   [min r1, r2, r3] !=x    -   Equivalent to: (r1!=x AND r2!=x AND r3!=x) OR (r1<x OR r2<x OR        r3<x)

In some embodiment, pre-defined or static synthetic min or max regionsmay be created before search time using the search system. Any number ofmethods are possible, including APIs or special operators. For oneimplementation specification of a synthetic region in a configurationfile may be allowed, as, for example:

-   -   MAXIMUM maxRegion region1 region2 region3

A user can then construct a query using the synthetic region namedmaxRegion. The equivalent in one embodiment of a query language wouldbe:

-   -   [region maxRegion]>25

The dynamically defined and static synthetic min/max regions may behavesubstantially identically from a search perspective. It should be notedthat in both cases, no additional physical region may be created; thusthere may be no penalty on a search index for a stored value orassociated index. In addition to searching for values, it is possible toretrieve values from the search index. For example, a search command:

-   -   SELECT region1, region2, region3 WHERE [max region1, region2,        region3]>25    -   would perform the search to find objects where the maximum        values of the three regions is greater than 25, and it would        also return the values of each region. Such capabilities may        allow the user (or an application invoking the search) to        inspect the regions and determine which one had the maximum        value that matched the query.

When a synthetic minimum or maximum region is pre-defined (e.g.,static), then one advantage may be that the effective maximum or minimumvalue that satisfied the query can be returned in the search results.For example:

-   -   SELECT maxRegion WHERE [region maxRegion]>25    -   may return only the maximum value of the regions that satisfied        the query. This in turn can potentially simplify the user        comprehension of the search results, or reduce the complexity of        an integrated application that would otherwise need to extract        the maximum value from each of the regions. An example of an        alternative syntax that could achieve the same result, but was        not implemented initially, may be to include the min or max        definitions directly in the SELECT portion of the query, along        these lines:    -   SELECT [min region1, region2, region3] WHERE [min        region1,region2,region3]<=“roger”

By implementing such searches as described above using a region valuesprocess, the region value search problem may be solved efficiently atthe process and search tree level as opposed to at the query level(e.g., by expanding the query automatically or constructing such a querymanually). Thus, using such a region value process, region valuesearching may be implemented in a manner that would be impossible to doat a query construction level. For example, even in the most simplifiedcase, a conventional manually constructed query will require on theorder of 2n−1 iterators. Using a region value process, only n iteratorsmay be required in such a simplified case, both speeding up the searchand reducing the computation resources required to implement such asearch.

Accordingly, embodiments may avoid the need to execute such huge queriesand provide many technical improvements in the functioning of thecomputer when applying such region value searching, including the use offewer computer resources such as disk, memory or processor cycles, andmay require less time to execute. Moreover, embodiments of such searchoperators may be usefully applied in a variety of contexts.

Before describing embodiments in detail, it may be helpful to discuss anexample of a search system. FIG. 2A depicts a block diagram illustratingan example of computing environment 200 having object repository 205,search system 201, and client computer 230. Object repository 205 maycomprise a file server or database system or other storage mechanismremotely or locally accessible by search system 201. Object repository205 may store objects 207 (e.g., documents, images, emails or otherobjects) that may be searchable by search system 201.

In the embodiment of FIG. 2A, search system 201 comprises a serverhaving central processing unit 212 connected to memory 214 and storageunit 218 via a bus. Central processing unit 212 may represent a singleprocessor, multiple processors, a processor(s) with multiple processingcores and the like. Storage unit 218 may include a non-transitorystorage medium such as hard disk drives, flash memory devices, opticalmedia and the like. Search system 201 may be connected to a datacommunications network such as the Internet, a local area network (LAN),a wide area network (WAN), a cellular network or some other network orcombination of networks.

Storage unit 218 stores computer executable instructions 219 and index224. Computer executable instructions 219 can represent multipleprograms or operating system code. In one embodiment, instructions 219are executable to provide object analyzer 220 and search engine 222.Object analyzer 220 and search engine 222 may be portions of the sameprogram or may be separate programs. According to one embodiment, forexample, object analyzer 220 is a component of a document managementsystem or content management system while search engine 222 is aseparate program that interfaces with the document or content managementsystem. Furthermore, object analyzer 220 and search engine 222 can beimplemented on different computing systems and can, themselves, bedistributed.

Index 224 may include metadata used to identify objects in response to asearch query and may also include text used to identify objects.Specifically, as discussed above the index 224 may include an invertedcopy of the indexed object. An inverted index may therefore contain aset of terms along with the an identification of which objects containthose terms Index 224 can include a single index containing metadata andtext, separate metadata and text indexes or other arrangements ofinformation. While shown as a single index, index 224 may includemultiple indices. Further, index 224 may be partitioned, with differentobjects being represented in each partition.

Client computer system 230 may include components similar to those ofthe server of search system 201, such as CPU 238, memory 236, andstorage 240. Additionally, client computer system 230 may includeexecutable instructions 232 to provide user interface 234 that allows auser to enter a search query. These instructions 232 may have, forexample, been provided by search system 201 in response to an access byclient computer 230. User interface 234 may be provided through a webbrowser, file system interface or other program.

Those skilled in the art will appreciate that search system 201 shown inFIG. 2A is merely an example of a computing system and embodiments of asearch system that may be implemented using other computing systems(e.g., desktop computers, laptops, mobile computing devices or othercomputing devices with adequate processing and memory) includingmultiple computers acting together to provide a search system (e.g., acluster of servers or other computing devices connected by a networkacting together to provide the search system). Similarly, clientcomputer 230 may include any suitable desktop computer, laptop, mobiledevice, server or other computing system.

In operation, object analyzer 220 may analyze objects in objectrepository 205 to determine information to be indexed in index 224. Whenan object 207 is added to search system 201, two types of informationare generally indexed, one or both full text and metadata. As anexample, suppose object 207 being added to search system 201 is a textfile. The text or content of the file is indexed as well as informationabout the file. In some cases, the metadata itself may include importantinformation associated with the object 207. This metadata may need itsown descriptive metadata indicating attributes of the metadata. In somecases, the metadata on its own without full text content is sufficientto represent an object. Object analyzer 220 can send indexinginstructions to search engine 222 to direct search engine 222 to add,modify, or delete metadata or text in index 224.

Object analyzer 220 may be a portion of a larger program, such as adocument or content management program, may be a separate program or maybe implemented according any suitable programming architecture. In oneembodiment, the process of determining metadata and text to be indexedmay be carried out by any number of different programs on a computersystem or distributed across computer systems. Detailed discussionsconcerning an example of an object analyzer can be found in U.S. patentapplication Ser. No. 13/595,570, filed Aug. 27, 2012, entitled “SYSTEMAND METHOD OF SEARCH INDEXES USING KEY-VALUE ATTRIBUTES TO SEARCHABLEMETADATA,” which is fully incorporated by reference herein.

When a search query is received at search system 201, search engine 222can search the information in index 224 to identify objects (content)207 responsive to the search query and return a list or otherrepresentation of those objects 207 to client computer 230.

FIG. 2B depicts a diagrammatic representation of one embodiment of anobject analyzer 220 for analyzing an object 207. Object analyzer 220 cancomprise various modules to process an object 207. Reading source datamodule 254 can open the object 207. Format identification module 256examines the object to determine what type of file or data the object207 comprises. Archive expansion module 258 unzips files or otherwisedecompresses files if the object 207 is a compressed file. Decryptionmodule 260 decrypts all or part of the data in the object 207. Textextraction module 262 applies rules to text in the object 207 to extracttext for index 224. Language detection module 264 examines the text todetermine the language in which the text is written. Classificationmodule 266 applies rules based upon text and metadata to classifycontent. Encoding module 268 can convert text to a supported encoding.Randomness detection module 270 can analyze data to be indexed to rejectrandom information.

Object analyzer 220 may include modules that can derive metadata forobject 207. For example, a document management system may provide alimited amount of metadata with the object 207. Object analyzer 220 canderive other metadata from the metadata provided, text or otherproperties of the object 207. As a specific example, a filter or pieceof code that extracts the text from a PowerPoint presentation might alsocreate metadata about the presentation. In this example, the metadatawhich is not provided by the document management system and which isderived by object analyzer 220 may include the number of slides in thepresentation, the title of the file, the name of the presentationauthor, or the size of paper the presentation was designed to print on.More complex examples of derived metadata might include statisticalanalysis to generate a list of keyword or key concepts in the document;determining the subject person or company of the text; sentimentanalysis—is the tone of the text positive or negative; or languageidentification—in what language is the text written. Further examples ofmetadata that may either be provided by the document management system(or other application) or derived by the analyzer may be the date theobject was created, the size of the object in bytes, the name of theobject, a description of the object or the like.

The embodiment of FIG. 2B is provided by way of example. Object analyzer220 may include any number of other modules to analyze an object andextract text 274 and metadata 272 to be indexed. Object analyzer 220 maybe a portion of a larger program, such as a document management program,may be a separate program or may be implemented according any suitableprogramming architecture. In one embodiment, the process of determiningmetadata 272 and text 274 to be indexed may be carried out by any numberof different programs on a computer system or distributed acrosscomputer systems.

Metadata 272 and text 274 thus processed by object analyzer 220 may beprovided to a search engine. An example search engine will now bedescribed with reference to FIG. 3 . Specifically, FIG. 3 depicts adiagrammatic representation of logical blocks for one embodiment ofsearch engine 322. Search engine 322 may provide indexing interface 300that receives indexing requests (e.g., from object analyzer 220) oranother source. A distributor module 310 may distribute the indexingrequests to indexing engines 320 that act on the indexing requests toupdate index 324. Search engine 322 may also include search interface330 to receive queries (e.g., from a user, a content server or othersource). Search interface 330 may send queries to search modules 340.These queries may be sent or distributed through federator 345 which mayserve as a coordinator for the search modules 340. Each of the searchmodules 340 may be a search process configured search the corpus basedon a related search term.

The coordinator may determine search modules (processes) 340 toinstantiate based on the terms of the received query and instantiatethose search modules 340. For example, the coordinator may define thesearch modules 340 and a hierarchy in order to define a search tree ofthe search modules 340 corresponding to the received query. Thecoordinator may then instantiate search modules 340 and provide eachmodule 340 with the data (e.g., related sub modules 340, search term forthe search module 340, etc.) needed to process the search tree. Thefederator 345 may then obtain results from one or more of the searchmodules 340 (e.g., the search module 340 that is a root node of thesearch tree) and generate a response to the query received throughsearch interface 330. This response may identify one or more responsiveobjects. Search modules 340 are responsible for implementing a termprocess for one or more terms using index 324 or implementing anoperator process for a search operator, a match iterator for matching avalue, an alternative iterator, a value iterator for all values in aregion, performing searches on an index partition, and performing taskssuch as computing relevance score, sorting results, and retrievingmetadata regions to return in a query. Thus, a search tree may include aset of hierarchically arranged search modules 340 as nodes of the searchtree, each search module 340 being a term process or an operatorprocess.

Search interface 330 may be configured to receive a search query from auser, and search index 324 for objects that meet the criteria set forthin the search query. Query languages may also be configured to permitsorting results of a search. Various rules may be used to determine thesort order. While users construct a search query, it should be notedthat the user could be any system that issues queries to the searchsystem, and may include other computer programs searching on behalf ofother users, creating reports or running automatic processes.Additionally, as described above, there can be many different types ofmetadata in the search index. Thus, the search queries are notrestricted to “text” based search terms.

In the context of this disclosure, the phrase “search term” represents atechnical concept or interpretation. For example, a search term in thecontext of this disclosure can be a word, a string, or any combinationof the following: phrases, numbers, strings, logical operations (e.g.,AND, OR, NOT, SUBSET, STEM, etc.), ordering or operations (e.g., usingparentheses), relationships (e.g., greater than, less than, not equalto, etc., similarities based on thesaurus, stemming, sounds-like, etc.,wildcards and pattern matching or the like. To this end, a search termcan also refer to any term that is used in a query and that has beenmodified or generated by any commonly used techniques. For context, asearch term could be a word “john” or a more complex expression like:

-   -   (>“bob” or !=(“123” or a*)) and (sounds-like “smith” or        thesaurus “doctor” or “medical doctor” or stem “medical”).

The embodiment of FIG. 3 is provided by way of example. Search engine322 may include any number of other modules or configurations to updateand search index 324. For example, search modules 340 and indexingengines 320 may be a single module. Search engine 322 may be a portionof a larger program, such as a document management program or contentmanagement system, may be a separate program or may be implementedaccording to any suitable programming architecture. Furthermore, theprocesses of search engine 322 may be distributed across multiplecomputer systems. Additionally, while in FIG. 3 , index 324 isillustrated as a single index, index 324 may comprise a set of smallerindexes. For example, a separate index can be used or updated by eachindexing engine

FIG. 4 depicts a diagrammatic representation of one embodiment ofregions or fields for a portion of index 324. Index 324 includes a listof some or all objects 207 in repository 205 (FIG. 2A), each identifiedby a unique identifier 401 (also referred to as object ID). Index 324further includes a set of metadata regions 400 (also referred to asmetadata fields). A metadata field 400 may include more than one entryfor an object. The metadata fields can each have associated values invalue storage locations within storage unit 218. In other embodiments,the values may be discarded. The index may include a list of dictionaryterms contained in the metadata values of the object and pointers towhere the metadata values corresponding to the field are stored. Index324 may also include other regions for an object, such as a text region402. Text region 402 may, for example, include a list of terms in thetext of an object. Index 324 may include some or all of the content ofan object.

While shown as a single index, index 324 may be partitioned. In indexpartitioning, in one embodiment, the index of objects in repository 205may be split into multiple indexes such that some objects are listed inone index partition, while other objects are listed in the other indexpartitions. As described below with reference to FIGS. 5 and 6 , a‘partition’ comprises a portion or fragment of index 324 and isassociated with indexing engine 320 and search module 340. Note that itis possible to copy a partition and associate a different index engineand search engine with this copied partition. Index partitioning mayalso reduce resource usage and search time. Furthermore, separateindexes may be maintained for metadata and text or different metadataregions or fields. Index 324 can be stored according to any suitablestorage scheme. Example storage schemes may include “Memory Storage,”“Disk Storage” and “Retrieval Storage”:

Memory Storage: in this storage scheme, all the elements of the indexare kept in memory. This provides the fastest operation when searchresults must be retrieved, since the memory storage mode minimizes diskactivity. Conversely, memory storage consumes the most memory inpartitions. For example, text regions which are frequently searched andretrieved for display may be held in memory.

Disk Storage: in this storage scheme, the dictionary and index are keptin memory, but the value storage is located on disk within a Checkpointfile. Keyword searches are still fast, but search queries which need toexamine the original data, such as phrase searches, are generallyslower. Retrieving values from disk for display is also slower. Forregions which are not commonly searched and displayed, disk storage maybe a desirable choice. Disk storage is also suitable as a storage modefor systems utilizing solid state hardware.

Retrieval Storage: in this storage scheme, storage is optimized for textmetadata regions which need to be retrieved and displayed, but do notneed to be searchable. As an example, text values may be stored on diskwithin the Checkpoint file, and there is no dictionary or index at all.This storage scheme can be used, for example, for regions such as HotPhrases and Summaries.

FIG. 5 depicts a diagrammatic representation of one embodiment of anindexing engine 320 to maintain a partition of index 324. Here, forexample, index 324 is divided into “n” partitions 500, with eachpartition including a metadata index 512, a text index 514 indexing aportion of the objects of the corpus and a stop word list 516 for eachbased on the objects of the corpus of objects associated with thatpartition 500 of the index 324 or all partitions 500 of the index 324.Thus, each stop word list 516 may be specific to the objects of thecorpus associated with that partition. A stop word list 516 may becreated at some time interval or based on some other condition. In thisembodiment, indexing engine 320 can include an indexing controller 505,a metadata update component 570, and a text update component 515. Inthis embodiment, index 324 is maintained as a separate metadata index512, which contains metadata for objects 207 in repository 205, and textindex 514, which contains content text from objects in repository 205,with a known relationship between the text and metadata components foreach object in the index.

Indexing controller 505 receives indexing requests (e.g., from adistributor, another application or other source). An indexing request510 received at the indexing controller 505 may include an instructionto add an object, delete an object, modify an object or replace anobject in index 324. Such an indexing request may also include theinformation to be added or changed, such as the full text content to beindexed and the associated metadata for the object. An indexing requestmay also contain derived metadata.

The text (derived text or full text content) of an indexing request 510may be a text file. It could be data exported from a database or otherinformation system. Commonly, the text is the human-readable informationwithin a document composed on a computer. In this scenario, a file suchas a Microsoft Word document would be analyzed by a filtering step toextract the text, which can be stripped of unnecessary information suchas fonts, styles, or page layout information.

The metadata portion of an indexing request 510 may specifically beprovided by an application providing the indexing request. This might bedata such as an identifier for the object, the date or time it was firstadded to the system, or the identity of the user who manages the object.

A portion of the metadata can be derived metadata. Derived metadata caninclude metadata inferred from the text content. For example, the filteror code that extracts the text from a PowerPoint presentation might alsocreate metadata about the presentation. In this example, the generatedmetadata may include the number of slides in the presentation, the titleof the file, the name of the presentation author stored in thePowerPoint file, or the size of paper the presentation was designed toprint on. More complex examples of derived metadata might includestatistical analysis to generate a list of keyword or key concepts inthe document, determining the subject person or company of the text,sentiment analysis (the positive or negative tone of the text), oridentification of the language in which the text is written. Derivedmetadata may also include data inferred from processing an object. Forexample, in processing a PowerPoint presentation, derived metadata mayinclude a timestamp of the time the PowerPoint was processed or thelocation where the PowerPoint presentation was processed.

An indexing engine can receive an indexing request 510 from anapplication, distributor or other source. Indexing request 510 specifiesan operation to be taken on index 324 for an object and any metadata ortext for that action. For context, an application that generates anindexing request may be a corporate document management system, a website with a search capability such as an online store, or a desktopsearch program for email.

According to one embodiment, for example, an indexing request can takethe form of an indexing object that includes a unique identification foran object, an operation, the metadata or text regions affected and themetadata and/or text for the index. By way of example, but notlimitation, indexing operations may include adding, replacing, modifyingand deleting information in the index, or combinations thereof. Thefollowing provides some exemplary operations that may be included inindexing requests.

AddOrReplace: this operation can be used to create new objects in theindex. According to one embodiment, if the object does not exist, itwill be created, but if an entry with the same object identificationexists, then it will be completely replaced with the new data,equivalent to a delete and add. This function may distinguish betweencontent and metadata. If an object already exists and metadata only isprovided, the existing full text content is retained.

AddOrModify: this operation will update an existing object or create anew object if it does not already exist. When modifying an existingobject, only the provided content and metadata is updated. Any metadataregions that already exist which are not specified in the AddOrModifycommand will be left intact.

Delete: this operation will remove an object from the index, includingboth the metadata and the content.

Indexing controller 505, according to one embodiment, is a componentwhich interprets the indexing request 510 to determine how it should beprocessed. Indexing controller 505 can identify whether a text indexingcommand exists, and if so, send the command with the necessaryparameters to the text update component 515. Indexing controller 505 canlikewise determine if any metadata indexing operations are required, andif so, send the command with necessary parameters to the metadata updatecomponent 570.

Text update component 515 is responsible for processing requests toindex full text content. This may include tasks such as maintaining adictionary of search terms, maintaining the internal search datastructures, and updating the storage representation of the text portionof the search index in memory or on disk as appropriate. Text updatecomponent 315 may support instructions such as Add an Object, Replace anObject, or Delete an Object.

Metadata update component 570 is responsible for processing requests toindex metadata 512 associated with an object in index 324. This mayinclude building and maintaining dictionaries of search terms,maintaining internal search data structures, and updating therepresentation of the metadata portion of the search index in memory oron disk as appropriate. Metadata update component 570 may supportinstructions such as Add an Object, Replace an Object, or Delete anObject.

The embodiment of FIG. 5 is provided by way of example. Indexing engine320 may include any number of other modules to update and search anindex. Indexing engine 320 may be a portion of a larger program, such asa document management program, may be a separate program or may beimplemented according any suitable programming architecture. In oneembodiment, the processes of indexing engine 320 may be distributedacross multiple computer systems.

As discussed above, an index may be partitioned. For example, in orderto scale to large sizes, the search index may be broken into partitions.When new objects are added to the search index, a method of determiningwhich partition should be the recipient of the new data is required. Forexample, one strategy may include allocating partitions based on amodulus of an object identifier (ID). As another example, a round-robintechnique may be used to add new objects to partitions which haveavailable capacity. One skilled in the art of computing will understandthat there may be many possible strategies.

FIG. 6 depicts a diagrammatic representation of one embodiment of system600 for managing partitions. In the embodiment of FIG. 6 , index 324 isdivided into “n” partitions 500, with each partition including ametadata index and a text index. As illustrated in FIG. 5 , in oneembodiment, each partition can have its own indexing engine 320 andsearch module 340.

A partition manager can be configured to manage these partitions.Partition manager 605 is a component of a search system that acceptsindexing requests, determines which partition should service an indexingrequest, and provides the indexing request to the appropriate indexingengine 320. In one embodiment, partition manager 605 can be a logicalfunction of a search engine in the search system which, in turn, can bepart of a document management system. In one embodiment, partitionmanager 605 can be a logical function of distributor 310 shown in FIG. 3. An indexing engine (e.g., indexing engine 320 shown in FIG. 3 ) for apartition performs the actual indexing operations of adding, deleting ormodifying data in the partition. Likewise, partition manager 605 may beable to federate search queries to multiple search engines 340associated with multiple partitions and combine the results. In oneembodiment, this function of partition manager 605 may be incorporatedin a federator (e.g., federator 345 shown in FIG. 3 ).

Returning then to FIG. 3 , in one embodiment, a search module 340 may beimplemented as an iterator. An iterator may be a process that returns anext object of the type of object for which the iterator is configured.Thus, an iterator may provide an interface or call (e.g., collectivelyreferred to as a “next interface”) to allow a requestor (e.g., anothersearch module 340 higher in the search tree or the coordinator) toaccess the interface of that iterator and obtain the next object of thecorpus that is responsive to the configuration of that iterator. Aniterator may maintain a pointer or other indicator that maintains anidentifier of the iterator's current position in the corpus such that itis the next responsive object in the corpus that is returned with eachnext call or a null indication (e.g., NULL, EOF, a maximum integervalue, etc.) if the iterator has reached the end of the corpus withoutidentifying a subsequent document responsive to the configuration ofthat iterator. An iterator may also be provided with a given object IDand be able to find a next object identifier starting with (e.g.,inclusive of) with the provided object ID.

For example, a search term iterator for a term may provide a nextinterface that provides the next object (e.g., next object identifier)in the corpus that contains that search term. An operator iterator mayprovide a next interface that provides the next object in the corpusthat meets the logical condition(s) specified by that operator withrespect to the search terms associated with that operator. A matchiterator may provide a next interface that can provide the next objectin the corpus that has a match for a given value in a correspondingregion. A match iterator may, for example, be configured with acomparator and a comparison value such that the next interface canprovide the next object in the corpus that has a match for the givenvalue in the corresponding region based on the comparator and thecomparison value. An alternative iterator may be a match iterator thatis associated with another match iterator that can provide the nextobject in the corpus that has a match for a given value in acorresponding region. A comparator and comparison value with which analternative iterator is configured may be based on the comparator of thematch iterator with which the alternative iterator is associated or, forexample, the region value operator of the search term.

In one embodiment then, search interface 330 may allow a user to use aregion value operator in a search query. This region value operator maytake almost any form desired and be utilized with other operatorstraditionally used with search queries as are known in the art. Theregion value operator may utilize almost any syntax desired to specify aprioritized evaluation of the values for a set of specified regionsagainst a value.

These search operators may allow the specification of minimum search ora maximum search. Such searches may specify a minimum (min) search or amaximum (max) search, a set of regions to be searched, a comparator toutilize (e.g., >,<, =, <=, >=, !=, etc.) and a comparison value. Thesesearch operators may be used to construct a synthetic region type in asearch engine. In other words, a region that may not be indexed orstored in the metadata for documents in a content management system.Such a synthetic region may be a multi-source region that is made up ofone or more traditional regions (e.g., regions that are indexed or whosevalues are otherwise stored in the metadata (or otherwise) for adocument in the content management system). Thus, values for thesynthetic region are not stored explicitly; rather, they are determinedby the underlying regions.

Such a region value term in a search may take the form of “region valueoperator”[“set or regions”] “search value”, where the “search value”includes a comparator (e.g., >,<, =, <=, >=, !=, etc.) and a comparisonvalue. Thus, for example, for a maximum search the search operatorsyntax may be as follows:

-   -   Maximum    -   [max r1, r2, r3 . . . ]>x; [max r1, r2, r3 . . . ]>=x; [max r1,        r2, r3 . . . ]<x; [max r1, r2, r3 . . . ] <=x; [max r1, r2,        r3]=x; or [max r1, r2, r3] !=x

For a minimum search the search operator syntax may be as follows:

-   -   Minimum    -   [min r1, r2, r3 . . . ]>x; [min r1, r2, r3 . . . ]>=x; [min r1,        r2, r3 . . . ]<x; [min r1, r2, r3 . . . ] <=x; [min r1, r2,        r3]=x; or [min r1, r2, r3] !=x

Thus, embodiments as disclosed may provide a simple syntax for users inthis situation. In certain embodiments, a maximum region operator willonly match at a given object if the maximum value of all the regions atthat particular object matches the search value (e.g., the comparisonvalue according to the comparator). Likewise, a minimum region requiresthe minimum of the regions to match at any given object. Othervariations on operators, syntaxes and uses are imaginable andcontemplated herein.

If such a region value term with a region value operator is specified ina received search query, federator 345 may instantiate a search module340 corresponding to the region value term or operator as a node in thesearch tree and a set of search modules 340 based on the regions of thereceived query. For example, federator 345 may define the search module340 and a hierarchy in order to define a search tree of the searchmodules 340 corresponding to the received query (or the portion ofthereof corresponding to the region value operator). The portion of thesearch tree defined by the federator 345 may include a region valueoperator search module 340 as a node in the search tree where thatregion value term or operator search module 340 has a match searchmodule 340 and a value search module 340 as a sub-node for each regionassociated with the subset operator in the search query.

To illustrate an example, referring briefly back to FIG. 1C, a searchtree for the region value search (e.g., search term) “[max FileModified,FileCreated, FormatDate, VersionCreated, DateManaged]<10 years” isdepicted. Here, operator process 120 may be a region operator (e.g.,“Max”) process instantiated by search module 340. Each match iteratorprocess 130 and alternative iterator process 140 for each region may bean iterator search module 340 that is a sub-node of the operator searchmodule 340 (e.g., implementing operator process 120). As will bediscussed in more detail, here there may be a match iterator andalternative iterator corresponding to each region specified in the “max”region operator, where each match iterator 130 is configured accordingto the comparison value 10 years value and the comparator (<).Similarly, each alternative iterator 140 is configured with thecomparison value 10 years but the comparator (>=). It will be noted thatthe search tree provided here is provided by way of illustrativeexample, as will be apparent from a review of this disclosure, othersearch trees for other instances of search trees for region value termsor operators may include fewer (or no) alternative iterators forregions, based for example on the comparator or region value operatorutilized in a region value search.

Referring again to FIG. 3 , in one embodiment, a region value operatorsearch module 340 may be implemented as an iterator. As used in a searchtree, such a region value iterator may have a number of sub-nodes, eachsub-node corresponding to a match iterator and an alternative iteratorfor one of the regions specified by the region value operator in theoriginal query. The region value iterator may have a set of regions anda search value including a comparator and a comparison value, such thatthe region value iterator will return an object (or identifier thereof)in response to a call to the next interface of the region value iteratorif the values in the set of regions for the object are true for thecomparison defined by the comparator, the comparison value and theregion operator. Specifically, for a maximum region value operator witha set of regions, a search value including a comparator and a comparisonvalue, a region value iterator may return an object if the maximum valuein the set of regions for the object (if a value exists in thoseregions) are true for the comparison defined by the comparator, thecomparison value and the region operator. For a minimum region valueoperator with a set of regions, a search value including a comparatorand a comparison value, a region value iterator may return an object ifthe minimum value in the set of regions for the object (if a valueexists in those regions) are true for the comparison defined by thecomparator, the comparison value and the region operator.

Referring now to FIG. 7 , one embodiment of a method for a region valueprocess (e.g., a region value iterator) is depicted. Such a region valueprocess may, for example, be implemented when a search tree is createdfor a search that includes a region value term. As may be recalled, theregions value term may have a region value operator (e.g., minimum ormaximum), a set of regions and a search value including a comparator anda comparison value. For purposes of explanation with respect to thisembodiment, it will be noted that a region iterator employing the methodof this embodiment will have some number of sub-nodes equal to thenumber of regions, each sub-node corresponding to a region identified inthe set of regions of a region value operator of a query. Each sub-nodeincludes a match iterator associated with the corresponding region andthe comparator and comparison value specified in the search value of theregion value operator. Each sub-node may also include an alternativeiterator (e.g., a match iterator) configured with the comparison valueand a different comparator. Each iterator has access to an index of acorpus of objects where each object is associated with an identifier.The identifiers of the objects in this embodiment may be sequential andeach iterator may maintain an indicator of a current object (which maybe initialized or set to a particular object identifier). An iteratorreturns the next document in the sequence in response to a call to theiterator's next interface if such an object exists, and an indicatorthat no more data remains otherwise (e.g., NULL, end, EOF, a max integervalue for the system, a particular count, a value storing the lastoffset, simply running out of data, etc.).

For example, for a match iterator, the next document (if it exists) witha higher identifier than the current indicator (assuming the identifiersare increasing in value) with a value in the corresponding region thatmatches the value specified in the query may be returned in response toa call to a match iterator's next interface. Similarly, as analternative iterator is a type of match iterator, for an alternativeiterator the next object (if it exists) that has any value in the regionassociated with the alternative iterator (again assuming the identifiersare increasing in value) may be returned in response to a call to thealternative iterator's next interface. For purposes of illustration withthis embodiment, it will be assumed objects have sequential numericalidentifiers greater than zero. In other embodiments, objects may justhave identifiers that are ordered and unique. It will be noted here,that when an iterator for a particular region is initialized to aparticular value for an object identifier, such an iterator may returnthe next object that has any value in the particular region associatedwith the value iterator inclusive of the initialized object identifier.Other variations may be imagined, such as ordering the objects usinglink lists, trees, arrays, or in some other manner.

Accordingly, a search that includes a region value term may be receivedwhere the region value term may identify a region value operator, a setof regions and a search value including a comparator and a comparisonvalue. This region value term may serve as the only term for a search ormay be part of a larger search query. In either instance, a region valueiterator may be created and provided with the region operator, the setof regions, and the search value including the comparator and thecomparison value. A current indicator (also referred to as a currentobject identifier) of the region value iterator may also be set to zero.At step 710, the match iterators that are sub-nodes of the region valueiterator may be created and initialized by setting the current objectindicator of each of the match iterators to zero. There may be one matchiterator for each region of the set of regions specified in the regionvalue operator such that each match iterator is provided with thecorresponding region and the search value including the comparator andthe comparison value. Additionally, at step 712, it can be determined ifany alternative iterators are needed for any of the match iterators foreach of the set of regions. This determination may be made based on theregion value operator (e.g., maximum or minimum) of the region valueterm or the comparator (e.g., >,<, =, <=, >=, !=, etc.) of the regionvalue term.

Below is a table depicting information that may be used by a regionvalue iterator to determine if any alternative iterators should becreated, and if so, what comparator should be used to initialize suchalternative iterators. As an example, with reference to the table, ifthe region value term has a “maximum” operator and the search valuespecifies “<” as the comparator, it can be determined that alternativeiterators are needed and the comparator to use with such alternativeiterators is “>=”.

Maximum Minimum Search Operator Alternative Alternative ComparatorIterators Comparator Iterators Comparator < (or <=) Yes >= (or >) No >(or >=) No Yes <= (or <) = Yes > Yes < != Yes > Yes <

When it is determined that alternative iterators are needed for matchiterators (Y branch of step 712) the alternative iterators that aresub-nodes of the region value iterator may be created and initialized atstep 720. There may be one alternative iterator for each region of theset of regions specified in the region value operator such that eachalternative iterator is associated with the match iterator for theregion and is configured with the determined comparator and the samecomparison value as specified in the region value term. Additionally,the current object indicator of each of the alternative iterators may beset to zero.

Loop 730 may be performed until each of the match iterators return a maxinteger value (e.g., or NULL, EOF, etc.) in response to a call to theirnext interfaces. At step 740 then, the next interface of each matchiterator whose current object indicator is equal to the current objectindicator of the region value iterator may be called. As will be noted,in the initial iteration of the loop, with both the current objectidentifier of the region value and the current object identifiers foreach match iterator initialized to an initial value (e.g., zero), thenext interface for each match iterator may be called at step 740.

Each match iterator called will return an object identifier for the nextobject that has a value in the region corresponding to that matchiterator that matched the search value (e.g., that returned true for acomparison with the comparison value based on the comparator) oralternatively a max integer value (or EOF, NULL, etc.) in the case nomore objects have values in the corresponding region that match thesearch value. At step 750, it can be determined if all the matchiterators have returned a max integer value, and if so, the regioniterator may return the list of matching object identifiers for theregion value query at step 742. If however, there is at least one matchiterator that returns an object identifier in response to the next call(or that has a current object indicator that is not a max integervalue), at step 752, the lowest object identifier for all the matchiterators (and the match iterators that returned this lowest objectidentifier) may be determined. The current object indicator for theregion value iterator can then be set to the lowest object identifierreturned by all of the match iterators.

At step 760, once all the match iterators that returned (or whosecurrent object indicator is equal to) the lowest object identifier aredetermined it can be determined if there are any alternative iteratorsassociated with the set of regions. If there are no alternativeiterators (N branch of step 760), it indicates that the values of theset of regions (e.g., as specified in the region value term) of theobject associated with the lower object identifier meet the search value(e.g., comparator and comparison value) of the region value term. Inthis case, the current object indicator for the region iterator (equalto the current object identifier) may be added to a list of objectidentifiers for objects matching the region value term at step 762. Theloop may then return to step 740 and the next interface of each matchiterator whose current index value is equal to the current objectidentifier may be called.

If there are alternative iterators (Y branch of step 760) associatedwith the set of regions it can then be determined, for the objectassociated with the current object identifier, if a value exists in anyregion of the set of regions of the search that does not meet the regionvalue operator and search value (e.g., comparator and comparison value)as specified in the region search term. In particular, the objectidentifier of each alternative iterator (or only those alternativeiterators associated with a match iterator or region for which a matchwas not found in step 750) may be initialized to the current objectidentifier at step 770 and the next interface of each alternativeiterator called at step 772. It will be noted here, that when thealternative iterator for a particular region is initialized to aparticular value for an object identifier, such an alternative iteratormay return the next object that has a matching value (e.g., based on thedetermined comparator and comparison value with which the alternativeiterator was configured) in the particular region associated with thealternative iterator inclusive of the initialized object identifier.Thus, for example, if an alternative iterator for the “DateModified”region is initialized to object identifier “2”, when the next identifierof this alternative iterator is called it will return object identifier“2” if the object associated with object identifier “2” has a valuepresent in the “DateModified” region that is a matching value. It willalso be noted that, in cases where the alternative iterator functions ina manner that is not inclusive of the initialized object identifier,each alternative iterator may be set to one less than the current objectidentifier (current object identifier—1) (again, in the example case ofsequential object identifiers for the corpus).

In response to the next call to each alternative iterator, the objectidentifiers for the next object that has a matching value (e.g., basedon the determined comparator and comparison value with which thealternative iterator was configured) in the particular region associatedwith the alternative iterator may be returned (if there any suchobjects, otherwise a maximum integer value, NULL, EOF, etc. may bereturned). At this point, it can be determined if the comparator for theregion vale search term was a “!=” comparator at step 778.

In cases where the comparator as specified in the region value searchterm was not a “!=” (N ranch of step 778), it can be determined if anyof the object identifiers returned from any alternative iterator areequal to the current object identifier at step 774. If any alternativeiterators returned an object identifier are equal to the current objectidentifier (Y branch of step 774) this indicates that a value exists ina region of the set of regions for the object that does not meet theregion value operator and search value (e.g., comparator and comparisonvalue) as specified in the region search term. No action may be takenhere, and the loop may then return to step 740 and the next interface ofeach match iterator whose current index value is equal to the currentobject identifier may be called.

If, however, there are no alternative iterators that returned an objectidentifier equal to the current object identifier (N branch of step774), it indicates that the values of the set of regions (e.g., asspecified in the region value term) of the object associated with thecurrent object identifier meet the search value (e.g., comparator andcomparison value) of the region value term. In this case, the currentobject indicator for the region iterator (equal to the current objectidentifier) may be added to a list of object identifiers for objectsmatching the region value term at step 776. The loop may then return tostep 740 and the next interface of each match iterator whose currentindex value is equal to the current object identifier may be called.

Returning then to step 778, of the comparator for the region valuesearch term was “!=” (Y branch of step 778) it can be determined at step780 if there are values for any of the set of regions of the objectcorresponding to the current object identifier that did not match thecomparator and comparison value as specified in the region value searchterm. Here, that determination can be made by determining if any matchiterator did not return the current object identifier. If there are nonon-matching regions (N branch of step 780), the current objectindicator for the region iterator (equal to the current objectidentifier) may be added to a list of object identifiers for objectsmatching the region value term at step 776. The loop may then return tostep 740 and the next interface of each match iterator whose currentindex value is equal to the current object identifier may be called.

If, however, there are non-matching regions for the current objectidentifier (Y branch of step 780), it can then be determined at step 782if any object identifier returned from any alternative iteratorcorresponding to any region that did match the comparator and comparisonvalue (e.g., for which a match iterator did return the current objectidentifier) returned the current object identifier. If so (Y branch ofstep 782), the current object indicator for the region iterator (equalto the current object identifier) may be added to a list of objectidentifiers for objects matching the region value term at step 776. Theloop may then return to step 740 and the next interface of each matchiterator whose current index value is equal to the current objectidentifier may be called.

It will be helpful to an understanding of certain embodiments toillustrate an embodiment with respect to a set of specific examples.Referring now to FIGS. 8A and 8B, a table including data useful forillustrating examples of a region value search is presented along with atable depicting matching objects for the examples that will bediscussed. It will be understood that these examples are discussed withrespect to certain embodiments of syntax and implementation and shouldnot be read to apply to embodiments as disclosed herein generally.

Example Searches for “Maximum” Region (Field) Operator

Example Region Value Search Term:

-   -   select . . . where [max field1, field2, field3, field4]>3 (or        select . . . where [region maxField]>3)    -   Here, this is a simple case, only match iterators are required.        If the value of at least one field of an object with a given        object identifier matches the search value (>3), then the object        corresponding to that identifier mates the region value term. If        it is desired to return or specify the matching field for the        object, all matching fields may be scanned for the largest        value.    -   In this example, as can be seen from FIG. 8B, Objects 2, 4, 6,        8, 9, 10, 12, 13, 14, 15, 16, 18, 19, 20 match.

Example Region Value Search Term:

-   -   select . . . where [max field1, field2, field3, field4]>=3 (or        select . . . where [region maxField]>=3)    -   Simple case, only match iterators required. If at least one        field matches at a given identifier, then there is a match for        that Object identifier. If it is desired to return or specify        the matching field for the object, all matching fields may be        scanned for the largest value.    -   In this example, as can be seen from FIG. 8B, Objects 2, 3, 4,        6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 19, 20 match.

Example Region Value Search Term:

-   -   select . . . where [max field1, field2, field3, field4]<3 (or        select . . . where [region maxField]<3)    -   This example of a region value term requires an alternative        iterator (e.g., configured according to comparator>=and a        comparison value of 3). If there is a match for any of these        alternative iterators for any of the set of regions (e.g.,        field1, field2, field3, field4) for an object identifier, the        object will not match the region value term.    -   If it is desired to return or specify the matching field for the        object, all matching fields may be scanned for the largest        value.    -   1. Find the first match:        -   a. Find the lowest matching object identifier in the            matching iterators. In this case it is Object 1.        -   b. Check that any fields that do not match at this            identifier, do not match on the alternative iterator (in            this case that the value is >=3). In this case all fields            match.        -   c. Return that Object 1 is a match.    -   2. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 2.        -   c. Check that any fields that do not match at this            identifier, do not match on the alternative iterator (in            this case that the value is >=3). In this case Field2            matches, so Object 2 is not a match.        -   d. Advance all iterators that are equal to the previously            matched identifier.        -   e. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 3.        -   f. Check that any fields that do not match at this            identifier, do not match on the alternative iterator (in            this case that the value is >=3). In this case Field1            matches, so Object 3 is not a match.        -   g. Advance all iterators that are equal to the previously            matched identifier.        -   h. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 4.        -   i. Check that any fields that do not match at this            identifier, do not match on the alternative iterator (in            this case that the value is >=3). In this case Field1            matches, so Object 4 is not a match.        -   j. Advance all iterators that are equal to the previously            matched identifier.        -   k. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 5.        -   l. Check that any fields that do not match at this ID, do            not match on the alternative iterator (in this case that the            value is >=3). In this case all fields match.        -   m. Return Object 5 is a match.    -   3. Continue until reaching the end of the iterators.        -   In this example, as can be seen from FIG. 8B, objects 1, 5,            17 match.

Example Region Value Search Term:

-   -   select . . . where [max field1, field2, field3, field4]<=3 (or        select . . . where [region maxField]<=3)    -   Like previous, except alternative Iterator is comparator> and        comparison value 3.    -   In this example, as can be seen from FIG. 8B, objects 1, 3, 5,        7, 11, 17 match.

Example Region Value Search Term:

-   -   select . . . where [max field1, field2, field3, field4]=3 (or        select . . . where [region maxField]=3)    -   This example of a region value term requires an alternative        iterator (e.g., configured according to comparator> and a        comparison value of 3). If there is a match for this iterator at        a given Object identifier, the Object identifier will not match.    -   If it is desired to return or specify the matching field for the        object, all matching fields may be scanned for the largest        value. In this case may use the any of the fields as they are        all the same.    -   1. Find the first match:        -   a. Find the lowest matching Object identifier in the            matching iterators. In this case, it is Object 3.        -   b. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is >3). In this example, all            non-matching fields pass the test for this Object            identifier.        -   c. Return that Object 3 is a match.    -   2. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 7.        -   c. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is >3). All non matching fields            pass the test for this Object identifier.        -   d. Return that Object 7 is a match.    -   3. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 8.        -   c. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is >3). Field4 fails the test for            this I Object identifier.        -   d. Advance all iterators that are equal to the previously            matched Object identifier.        -   e. Find the first occurrence of the lowest matching Object            ID. In this case, it's Object 9.        -   f. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is >3). Field1 fails the test for            this Object identifier.        -   g. Advance all iterators that are equal to the previously            matched Object identifier.        -   h. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 10.        -   i. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is >3). Field2 fails the test for            this Object identifier.        -   j. Advance all iterators that are equal to the previously            matched Object identifier.        -   k. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 11.        -   l. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is >3). All fields pass the test            for this Object identifier.        -   m. Return Object 11 is a match.    -   4. Continue in this manner until reaching the end of the        iterators.        -   In this example, as can be seen from FIG. 8B, Objects 3, 7,            11 are responsive to the region value term.

Example Region Value Search Term:

-   -   select . . . where [max field1, field2, field3, field4] !=3 (or        select . . . where [region maxField] !=3)    -   This example of a region value term requires an alternative        iterator (configured according to comparator> and a comparison        value of 3). If all fields do not match the match iterator, then        at least one of them must match the alternative iterator or else        it is not a match.    -   If it is desired to return or specify the matching field for the        object, all matching fields may be scanned for the largest        value.    -   1. Find the first match:        -   a. Find the lowest matching Object identifier in the            matching iterators. In this case, it is Object 1.        -   b. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (>3). There are no non-matching fields.        -   c. Return that Object 1 is a match.    -   2. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 2.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (>3). There are no non-matching fields.        -   d. Return that Object 2 is a match.    -   3. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 3.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (>3). It does not.        -   d. Advance all iterators that are equal to the previously            matched Object identifier.        -   e. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 4.        -   f. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (>3). There are no non-matching fields.        -   g. Return that Object 4 is a match.    -   4. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 5.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (>3). There are no non-matching fields.        -   d. Return that Object 5 is a match.    -   5. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 6.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (>3). There are no non-matching fields.        -   d. Return that Object 6 is a match.    -   6. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 7.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (>3). In this example, they do not.        -   d. Advance all iterators that are equal to the previously            matched Object identifier.        -   e. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 8.        -   f. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (e.g., >3). Here, Field4 matches for its alternative            iterator.        -   g. Return that Object 8 is a match.    -   As can be seen, the region value iterator may continue on in        this manner until the iterators return a maximum integer value,        NULL, EOF, or the like.    -   In this example, as can be seen from FIG. 8B, objects 1, 2, 4,        5, 6, 8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 19, 10 match.

Example Searches for “Minimum” Region (Field) Operator

Example Region Value Search Term:

-   -   select . . . where [min field1, field2, field3, field4]<3 (or        select . . . where [region minField]<3)    -   Simple case, only match iterators required. If at least one        field matches at a given Object identifier, then there is a        match for that Object identifier. If it is desired to return or        specify the matching field for the object, all matching fields        may be scanned for the smallest value.    -   In this example, as can be seen from FIG. 8B, objects 1, 2, 3,        4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 18 match.

Example Region Value Search Term:

-   -   select . . . where [min field1, field2, field3, field4]<=3 (or        select . . . where [region minField]<=3)    -   Simple case, only match iterators required. If at least one        field matches at a given id, then there is a match for that id.        If it is desired to return or specify the matching field for the        object, all matching fields may be scanned for the smallest        value.    -   In this example, as can be seen from FIG. 8B, objects 1, 2, 3,        4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 match.

Example Region Value Search Term:

-   -   select . . . where [min field1, field2, field3, field4]>3 (or        select . . . where [region minField]>3)    -   This example of a region value term requires an alternative        iterator configured according to comparator<=and a comparison        value of 3). If there is a match for this iterator at a given        Object identifier, the Object identifier will not match.    -   If matching field is desired, scan all matching fields for the        smallest value.    -   1. Find the first match:        -   a. Find the lowest matching Object identifier in the            matching iterators. In this case, it's Object 2.        -   b. Check that any fields that do not match at this ID, do            not match on the alternative iterator (in this case that the            value is <=3). Field1 matches the alternative iterator, so            Object 2 is not a match.        -   c. Advance all iterators that are equal to the previously            matched Object identifier.        -   d. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 4.        -   e. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field3            matches, so Object 4 is not a match.        -   f. Advance all iterators that are equal to the previously            matched Object identifier.        -   g. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 6.        -   h. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field1            matches, so Object 6 is not a match.        -   i. Advance all iterators that are equal to the previously            matched Object identifier.        -   j. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 8        -   k. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field3            matches, so Object 8 is not a match.        -   l. Advance all iterators that are equal to the previously            matched Object identifier.        -   m. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 9.        -   n. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field2            matches, so Object 9 is not a match.        -   o. Advance all iterators that are equal to the previously            matched Object identifier.        -   p. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 10.        -   q. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field3            matches, so Object 10 is not a match.        -   r. Advance all iterators that are equal to the previously            matched Object identifier.        -   s. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 12.        -   t. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field1            matches, so Object 12 is not a match.        -   u. Advance all iterators that are equal to the previously            matched Object identifier.        -   v. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 13.        -   w. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field1            matches, so Object 13 is not a match.        -   x. Advance all iterators that are equal to the previously            matched Object identifier.        -   y. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 14.        -   z. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field4            matches, so Object 14 is not a match.        -   aa. Advance all iterators that are equal to the previously            matched Object identifier.        -   bb. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 15.        -   cc. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field2            matches, so Object 15 is not a match.        -   dd. Advance all iterators that are equal to the previously            matched Object identifier.        -   ee. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 16.        -   ff. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field1            matches, so Object 16 is not a match.        -   gg. Advance all iterators that are equal to the previously            matched Object identifier.        -   hh. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 18.        -   ii. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field1            matches, so Object 18 is not a match.        -   jj. Advance all iterators that are equal to the previously            matched Object identifier.        -   kk. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 19.        -   ll. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). In this case Field2            matches, so Object 19 is not a match.        -   mm. Advance all iterators that are equal to the previously            matched Object identifier.        -   nn. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 20.        -   oo. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <=3). No Fields match the            alternative iterator.        -   pp. Return Object 20 is a match.    -   Objects 20 match

Example Region Value Search Term:

-   -   select . . . where [min field1, field2, field3, field4]>=3 (or        select . . . where [region minField]>=3)    -   Like previous, except alternative Iterator search value has a        comparator of < and a comparison value of 3.    -   In this example, as can be seen from FIG. 8B, Objects 15, 19, 20        match.

Example Region Value Search Term:

-   -   select . . . where [min field1, field2, field3, field4]=3 (or        select . . . where [region minField]=3)    -   This example of a region value term requires an alternative        iterator (configured according to comparator<and a comparison        value of 3). If there is a match for this iterator at a given        Object identifier, the Object identifier will not match.    -   If matching field is desired, scan all matching fields for the        smallest value.    -   1. Find the first match:        -   a. Find the lowest matching Object identifier in the            matching iterators. In this case, it's Object 3.        -   b. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). Field 3 matches the            alternative iterator.        -   c. Advance all iterators that are equal to the previously            matched Object identifier.        -   d. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 7.        -   e. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). Field1 matches the            alternative iterator.        -   f. Advance all iterators that are equal to the previously            matched Object identifier.        -   g. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 8.        -   h. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). Field3 matches the            alternative iterator.        -   i. Advance all iterators that are equal to the previously            matched Object identifier.        -   j. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 9.        -   k. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). Field2 matches the            alternative iterator.        -   l. Advance all iterators that are equal to the previously            matched Object identifier.        -   m. Find the first occurrence of the lowest matching Object            ID. In this case, it's Object 10.        -   n. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). Field4 matches the            alternative iterator.        -   o. Advance all iterators that are equal to the previously            matched Object identifier.        -   p. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 11.        -   q. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). Field1 matches the            alternative iterator.        -   r. Advance all iterators that are equal to the previously            matched Object identifier.        -   s. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 12.        -   t. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). Field1 matches the            alternative iterator.        -   u. Advance all iterators that are equal to the previously            matched Object identifier.        -   v. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 13.        -   w. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). Field2 matches the            alternative iterator.        -   x. Advance all iterators that are equal to the previously            matched Object identifier.        -   y. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 15.        -   z. Check that any fields that do not match at this Object            identifier, do not match on the alternative iterator (in            this case that the value is <3). No Field matches            alternative iterator.        -   aa. Return that Object 15 is a match.    -   The region value iterator may continue on in this manner until        the iterators return a maximum integer value, NULL, EOF, or the        like.    -   In this example, as can be seen from FIG. 8B, Objects 15, 19 are        matches.

Example Region Value Search Term:

-   -   select . . . where [min field1, field2, field3, field4] !=3 (or        select . . . where [region minField] !=3)    -   This example of a region value term requires an alternative        iterator configured according to comparator<and a comparison        value of 3. If all fields do not match the match iterator, than        at least one of them must match the alternative iterator or else        it is not a match.    -   If matching field is required, scan all matching fields for the        smallest.    -   1. Find the first match:        -   a. Find the lowest matching Object identifier in the            matching iterators. In this case, it's Object 1.        -   b. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (<3). There are no non-matching fields.        -   c. Return that Object 1 is a match.    -   2. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 2.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (<3). There are no non-matching fields.        -   d. Return that Object 2 is a match.    -   3. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 3.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (<3). Field3 matches the alternative iterator.        -   d. Return that Object 3 is a match.    -   4. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 4.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (<3). Here, there are no non-matching fields.        -   d. Return that Object 4 is a match.    -   5. Continue to the next match:        -   a. Advance all iterators that are equal to the previously            matched Object identifier.        -   b. Find the first occurrence of the lowest matching Object            identifier. In this case, it's Object 2.        -   c. Check that if there are non-matching fields, at least one            of the matching fields matches on the alternative iterator            (<3). There are no non-matching fields.        -   d. Return that Object 2 is a match.    -   As can be seen, here, the region value iterator may continue on        in this manner until the iterators return a maximum integer        value, NULL, EOF, or the like.    -   In this example, as can be seen from FIG. 8B, Objects 1, 2, 4,        5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 18, 20 match.

Although the invention has been described with respect to specificembodiments thereof, these embodiments are merely illustrative, and notrestrictive of the invention. The description herein of illustratedembodiments of the invention, including the description in the Abstractand Summary, is not intended to be exhaustive or to limit the inventionto the precise forms disclosed herein. Rather, the description isintended to describe illustrative embodiments, features and functions inorder to provide a person of ordinary skill in the art context tounderstand the invention without limiting the invention to anyparticularly described embodiment, feature or function, including anysuch embodiment feature or function described in the Abstract orSummary. While specific embodiments of, and examples for, the inventionare described herein for illustrative purposes only, various equivalentmodifications are possible within the spirit and scope of the invention,as those skilled in the relevant art will recognize and appreciate. Asindicated, these modifications may be made to the invention in light ofthe foregoing description of illustrated embodiments of the inventionand are to be included within the spirit and scope of the invention.Thus, while the invention has been described herein with reference toparticular embodiments thereof, a latitude of modification, variouschanges and substitutions are intended in the foregoing disclosures, andit will be appreciated that in some instances some features ofembodiments of the invention will be employed without a correspondinguse of other features without departing from the scope and spirit of theinvention as set forth. Therefore, many modifications may be made toadapt a particular situation or material to the essential scope andspirit of the invention.

Reference throughout this specification to “one embodiment”, “anembodiment”, or “a specific embodiment” or similar terminology meansthat a particular feature, structure, or characteristic described inconnection with the embodiment is included in at least one embodimentand may not necessarily be present in all embodiments. Thus, respectiveappearances of the phrases “in one embodiment”, “in an embodiment”, or“in a specific embodiment” or similar terminology in various placesthroughout this specification are not necessarily referring to the sameembodiment. Furthermore, the particular features, structures, orcharacteristics of any particular embodiment may be combined in anysuitable manner with one or more other embodiments. It is to beunderstood that other variations and modifications of the embodimentsdescribed and illustrated herein are possible in light of the teachingsherein and are to be considered as part of the spirit and scope of theinvention.

In the description herein, numerous specific details are provided, suchas examples of components and/or methods, to provide a thoroughunderstanding of embodiments of the invention. One skilled in therelevant art will recognize, however, that an embodiment may be able tobe practiced without one or more of the specific details, or with otherapparatus, systems, assemblies, methods, components, materials, parts,and/or the like. In other instances, well-known structures, components,systems, materials, or operations are not specifically shown ordescribed in detail to avoid obscuring aspects of embodiments of theinvention. While the invention may be illustrated by using a particularembodiment, this is not and does not limit the invention to anyparticular embodiment and a person of ordinary skill in the art willrecognize that additional embodiments are readily understandable and area part of this invention.

Embodiments discussed herein can be implemented in a computercommunicatively coupled to a network (for example, the Internet),another computer, or in a standalone computer. As is known to thoseskilled in the art, a suitable computer can include a CPU, at least oneread-only memory (“ROM”), at least one random access memory (“RAM”), atleast one hard drive (“HD”), and one or more input/output (“I/O”)device(s). The I/O devices can include a keyboard, monitor, printer,electronic pointing device (for example, mouse, trackball, stylus, touchpad, etc.), or the like.

ROM, RAM, and HD are computer memories for storing computer-executableinstructions executable by the CPU or capable of being compiled orinterpreted to be executable by the CPU. Suitable computer-executableinstructions may reside on a computer readable medium (e.g., ROM, RAM,and/or HD), hardware circuitry or the like, or any combination thereof.Within this disclosure, the term “computer readable medium” is notlimited to ROM, RAM, and HD and can include any type of data storagemedium that can be read by a processor. For example, a computer-readablemedium may refer to a data cartridge, a data backup magnetic tape, afloppy diskette, a flash memory drive, an optical data storage drive, aCD-ROM, ROM, RAM, HD, or the like. The processes described herein may beimplemented in suitable computer-executable instructions that may resideon a computer readable medium (for example, a disk, CD-ROM, a memory,etc.). Alternatively, the computer-executable instructions may be storedas software code components on a direct access storage device array,magnetic tape, floppy diskette, optical storage device, or otherappropriate computer-readable medium or storage device.

Any suitable programming language can be used to implement the routines,methods or programs of embodiments of the invention described herein,including C, C++, Java, JavaScript, HTML, or any other programming orscripting code, etc. Other software/hardware/network architectures maybe used. For example, the functions of the disclosed embodiments may beimplemented on one computer or shared/distributed among two or morecomputers in or across a network. Communications between computersimplementing embodiments can be accomplished using any electronic,optical, radio frequency signals, or other suitable methods and tools ofcommunication in compliance with known network protocols.

Different programming techniques can be employed such as procedural orobject oriented. Any particular routine can execute on a single computerprocessing device or multiple computer processing devices, a singlecomputer processor or multiple computer processors. Data may be storedin a single storage medium or distributed through multiple storagemediums, and may reside in a single database or multiple databases (orother data storage techniques). Although the steps, operations, orcomputations may be presented in a specific order, this order may bechanged in different embodiments. In some embodiments, to the extentmultiple steps are shown as sequential in this specification, somecombination of such steps in alternative embodiments may be performed atthe same time. The sequence of operations described herein can beinterrupted, suspended, or otherwise controlled by another process, suchas an operating system, kernel, etc. The routines can operate in anoperating system environment or as stand-alone routines. Functions,routines, methods, steps and operations described herein can beperformed in hardware, software, firmware or any combination thereof.

Embodiments described herein can be implemented in the form of controllogic in software or hardware or a combination of both. The controllogic may be stored in an information storage medium, such as acomputer-readable medium, as a plurality of instructions adapted todirect an information processing device to perform a set of stepsdisclosed in the various embodiments. Based on the disclosure andteachings provided herein, a person of ordinary skill in the art willappreciate other ways and/or methods to implement the invention.

It is also within the spirit and scope of the invention to implement insoftware programming or code any of the steps, operations, methods,routines or portions thereof described herein, where such softwareprogramming or code can be stored in a computer-readable medium and canbe operated on by a processor to permit a computer to perform any of thesteps, operations, methods, routines or portions thereof describedherein. The invention may be implemented by using software programmingor code in one or more general purpose digital computers, by usingapplication specific integrated circuits, programmable logic devices,field programmable gate arrays, optical, chemical, biological, quantumor nanoengineered systems, components and mechanisms may be used. Ingeneral, the functions of the invention can be achieved by any means asis known in the art. For example, distributed or networked systems,components and circuits can be used. In another example, communicationor transfer (or otherwise moving from one place to another) of data maybe wired, wireless, or by any other means.

A “computer-readable medium” may be any medium that can contain, store,communicate, propagate, or transport the program for use by or inconnection with the instruction execution system, apparatus, system ordevice. The computer readable medium can be, by way of example only butnot by limitation, an electronic, magnetic, optical, electromagnetic,infrared, or semiconductor system, apparatus, system, device,propagation medium, or computer memory. Such computer-readable mediumshall generally be machine readable and include software programming orcode that can be human readable (e.g., source code) or machine readable(e.g., object code). Examples of non-transitory computer-readable mediacan include random access memories, read-only memories, HDs, datacartridges, magnetic tapes, floppy diskettes, flash memory drives,optical data storage devices, CD-ROMs, and other appropriate computermemories and data storage devices. In an illustrative embodiment, someor all of the software components may reside on a single server computeror on any combination of separate server computers. As one skilled inthe art can appreciate, a computer program product implementing anembodiment disclosed herein may comprise one or more non-transitorycomputer readable media storing computer instructions translatable byone or more processors in a computing environment.

A “processor” includes any hardware system, mechanism or component thatprocesses data, signals or other information. A processor can include asystem with a general-purpose CPU, multiple processing units, dedicatedcircuitry for achieving functionality, or other systems. Processing neednot be limited to a geographic location, or have temporal limitations.For example, a processor can perform its functions in “real-time,”“offline,” in a “batch mode,” etc. Portions of processing can beperformed at different times and at different locations, by different(or the same) processing systems.

It will also be appreciated that one or more of the elements depicted inthe drawings/figures can also be implemented in a more separated orintegrated manner, or even removed or rendered as inoperable in certaincases, as is useful in accordance with a particular application.Additionally, any signal arrows in the drawings/Figures should beconsidered only as exemplary, and not limiting, unless otherwisespecifically noted.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having,” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,product, article, or apparatus that comprises a list of elements is notnecessarily limited only those elements but may include other elementsnot expressly listed or inherent to such process, product, article, orapparatus.

Furthermore, the term “or” as used herein is generally intended to mean“and/or” unless otherwise indicated. For example, a condition A or B issatisfied by any one of the following: A is true (or present) and B isfalse (or not present), A is false (or not present) and B is true (orpresent), and both A and B are true (or present). As used herein, thatfollow, a term preceded by “a” or “an” (and “the” when antecedent basisis “a” or “an”) includes both singular and plural of such term, unlessclearly indicated otherwise (i.e., that the reference “a” or “an”clearly indicates only the singular or only the plural). Also, as usedin the description herein the meaning of “in” includes “in” and “on”unless the context clearly dictates otherwise.

Although the foregoing specification describes specific embodiments,numerous changes in the details of the embodiments disclosed herein andadditional embodiments will be apparent to, and may be made by, personsof ordinary skill in the art having reference to this disclosure. Inthis context, the specification and figures are to be regarded in anillustrative rather than a restrictive sense, and all such modificationsare intended to be included within the scope of this disclosure.

What is claimed is:
 1. A search system, comprising: a processor; and anon-transitory computer readable medium, having instructions executableon the processor for: receiving a search query having a region valueterm, the region value term including a region value operator, a set ofregions and a first search value including a first comparator and afirst comparison value; generating a search tree for the region valueterm, the search tree having a region value node configured according tothe region value operator, the set of regions and the first searchvalue, wherein the region value node has, for each region of the set ofregions, a sub-node comprising a first match process corresponding tothe region and the first search value; determining whether anyalternative processes are needed based on the region value operator andthe first comparator; responsive to determining that alternativeprocesses are needed, including each alternative process in a sub-nodeof the search tree for a corresponding region, the alternative processcorresponding to the region and a second search value including a secondcomparator and the first comparison value, the second comparatordetermined based on the region value operator and the first comparator;executing the search tree using an index of a corpus to determine one ormore objects of the corpus that satisfy the region value term, thecorpus comprising a set of objects, each object associated with acorresponding identifier; and returning the identifiers for the one ormore objects of the corpus that satisfy the region value operator. 2.The search system of claim 1, wherein each of the match processes is amatch iterator configured to evaluate the objects of the corpusaccording to an order of the identifiers of the objects.
 3. The searchsystem of claim 2, wherein the order of the identifiers is sequential.4. The search system of claim 3, wherein the region value node isconfigured to call each of the match processes to determine a result forthat match process.
 5. The search system of claim 4, wherein each of thealternative processes is a second match iterator configured to beinitialized with an object identifier and evaluate the objects of thecorpus according to the corresponding region and a second result fromthe second match iterator is the identifier of any next objectcontaining a value in the corresponding region matching the secondsearch value.
 6. The search system of claim 5, wherein the region valueoperator is a maximum operator for determining whether a maximum valuein the set of regions for the object meets the search value or a minimumoperator for determining whether a minimum value in the set of regionsfor the object meets the search value.
 7. A non-transitory computerreadable medium, comprising instructions for: receiving a search queryhaving a region value term, the region value term including a regionvalue operator, a set of regions and a first search value including afirst comparator and a first comparison value; generating a search treefor the region value term, the search tree having a region value nodeconfigured according to the region value operator, the set of regionsand the first search value, wherein the region value node has, for eachregion of the set of regions, a sub-node comprising a first matchprocess corresponding to the region and the first search value;determining whether any alternative processes are needed based on theregion value operator and the first comparator; responsive todetermining that alternative processes are needed, including eachalternative process in a sub-node of the search tree for a correspondingregion, the alternative process corresponding to the region and a secondsearch value including a second comparator and the first comparisonvalue, the second comparator determined based on the region valueoperator and the first comparator; executing the search tree using anindex of a corpus to determine one or more objects of the corpus thatsatisfy the region value term, the corpus comprising a set of objects,each object associated with a corresponding identifier; and returningthe identifiers for the one or more objects of the corpus that satisfythe region value operator.
 8. The non-transitory computer readablemedium of claim 7, wherein each of the match processes is a matchiterator configured to evaluate the objects of the corpus according toan order of the identifiers of the objects.
 9. The non-transitorycomputer readable medium of claim 8, wherein the order of theidentifiers is sequential.
 10. The non-transitory computer readablemedium of claim 9, wherein the region value node is configured to calleach of the match processes to determine a result for that matchprocess.
 11. The non-transitory computer readable medium of claim 10,wherein each of the alternative processes is a second match iteratorconfigured to be initialized with an object identifier and evaluate theobjects of the corpus according to the corresponding region and a secondresult from the second match iterator is the identifier of any nextobject containing a value in the corresponding region matching thesecond search value.
 12. The non-transitory computer readable medium ofclaim 11, wherein the region value operator is a maximum operator fordetermining whether a maximum value in the set of regions for the objectmeets the search value or a minimum operator for determining whether aminimum value in the set of regions for the object meets the searchvalue.
 13. A method, comprising: receiving a search query having aregion value term, the region value term including a region valueoperator, a set of regions and a first search value including a firstcomparator and a first comparison value; generating a search tree forthe region value term, the search tree having a region value nodeconfigured according to the region value operator, the set of regionsand the first search value, wherein the region value node has, for eachregion of the set of regions, a sub-node comprising a first matchprocess corresponding to the region and the first search value;determining whether any alternative processes are needed based on theregion value operator and the first comparator; responsive todetermining that alternative processes are needed, including eachalternative process in a sub-node of the search tree for a correspondingregion, the alternative process corresponding to the region and a secondsearch value including a second comparator and the first comparisonvalue, the second comparator determined based on the region valueoperator and the first comparator; executing the search tree using anindex of a corpus to determine one or more objects of the corpus thatsatisfy the region value term, the corpus comprising a set of objects,each object associated with a corresponding identifier; and returningthe identifiers for the one or more objects of the corpus that satisfythe region value operator.
 14. The method of claim 13, wherein each ofthe match processes is a match iterator configured to evaluate theobjects of the corpus according to an order of the identifiers of theobjects.
 15. The method of claim 14, wherein the order of theidentifiers is sequential.
 16. The method of claim 15, wherein theregion value node is configured to call each of the match processes todetermine a result for that match process.
 17. The method of claim 16,wherein each of the alternative processes is a second match iteratorconfigured to be initialized with an object identifier and evaluate theobjects of the corpus according to the corresponding region and a secondresult from the second match iterator is the identifier of any nextobject containing a value in the corresponding region matching thesecond search value.
 18. The method of claim 17, wherein the regionvalue operator is a maximum operator for determining whether a maximumvalue in the set of regions for the object meets the search value or aminimum operator for determining whether a minimum value in the set ofregions for the object meets the search value.